The following profile proforma (PPF) defines the WebCGM application
profile for CGM files with a comparison to the ISO Model Profile as defined
in ISO/IEC 8632:1999. The tables for the ISO Model Profile are duplicated
here for reference and are intended to be accurate. In case of discrepancies,
the Model Profile in ISO/IEC 8632:1999 shall take precedence. In the PPF,
there are references such as 9.5.4.5, 7.5.11, and Annex I, etc. These are
references to sections of the CGM:1999 text, from which this proforma is
extracted. Other internal PPF references look like T.16.13 and Attachment
26.3, which are references to table entries in the PPF itself.

The Model Profile (in the ISO CGM:1999 text) uses check boxes to indicate
whether an item is required, permitted, or prohibited in metafiles conforming
to the Model Profile. Authors of cascading profiles should be aware that the
Model Profile does not have all three possible choices for each item, and
that alternate choices are indicated here in the tables with "No" and the
"checked" choice is indicated with "Yes." For example, this rule "Element is:
Required Yes; Permitted No;" means that the element is required in all
metafiles conforming to WebCGM 2.0 and that authors of cascading profiles
could choose to make the element optional (Permitted), but they must not
prohibit the element.

If permitted, graphical meaning of the degeneracy: A line
primitive element, whose entire locus is a single point, denotes a
graphical dot which is a filled circle, with diameter equal to the
current line width and colour equal to the current line
colour.

If permitted, graphical meaning of the degeneracy: A
filled-area primitive element, whose entire locus is either a single
point or a line has the following meaning:

- If the locus of a filled-area primitive is a single point,
then the meaning is a dot (which is a filled circle).

- If the locus of a filled-area primitive is a
non-degenerate line segment, then the meaning is a line.

The dot or line is displayed with the fill colour if EDGE
VISIBILITY is 'off', unless INTERIOR STYLE is 'empty', in which case
it is not rendered. If EDGE VISIBILITY is 'on', the interior
treatment is the dot or line displayed in the fill colour, and then a
dot or line superimposed with the current edge attributes.

Other: None.

T.14.4

Same as Model Profile:
No

Graphical text strings

References:

9.5.4.5

Minimum string length (bytes):
0

Maximum string length (bytes): 254

Any restrictions on the use of ISO/IEC 2022 switching controls?

The C0 character NUL (code value) is permitted and has no
effect. String parameters of graphical text shall contain no control
character (7/8 bit codes: 1-31 and 128-159). ISO/IEC 2022 switching
is not allowed in graphical text. A valid WebCGM metafile may use for
graphical text only the character
encodings (CGM "character sets"): the collection of four
character encodings which comprise ISO Latin1 and Symbol (see
CHARACTER SET LIST); Unicode UTF-8; and UTF-16.

Other: None.

Note. According to the Binary Encoding of CGM:1999, strings of
multi-byte Unicode text are "big-endian", like the rest of the binary
metafile.

Minimum string length (bytes): 0.

Maximum string length (bytes): 254.

Any restrictions on the use of ISO/IEC 2022 switching controls?
C0 control codes (except NUL and ISO/IEC 2022 switching)
are prohibited.

Any character set used in the metafile which is accessed by
ISO/IEC 2022 switching techniques shall be in the Character Set List
(defined in this profile).

Note: according to CGM:1999, the format effectors are NUL, CR, LF,
BS, HT, VT, and FF.

Other C0 control codes (except NUL and ISO/IEC 2022 switching) are
prohibited.

Any limits on the set of acceptable character
encodings (CGM "character sets")? The permitted character
encodings (CGM "character sets") for non-graphical text are ISO
Latin 1 (LHS & RHS), and UNICODE UTF-8, and Unicode UTF-16. Only
one of these three shall be used throughout any particular WebCGM
metafile instance. According to the CGM standard, the default SF
character encoding ("set"), at the beginning of the 'metafile id'
parameter of the BEGIN METAFILE element is ISO Latin 1. If the
metafile is to use UTF-8 for SF parameters, then the following
4-octet ISO 2022 sequence shall occur as the first 4 octets of the
'metafile id' parameter:

ESC 2/5 2/15 4/9

If the metafile is to use UTF-16 for SF parameters, then the
following 4-octet ISO 2022 sequence shall occur as the first 4 octets
of the 'metafile id' parameter:

ESC 2/5 2/15 4/12

Otherwise, the use of ISO 2022 switching is prohibited in
non-graphical text string.

NOTE: Section 6.3.4.5 of CGM:1999 allows the switching to
UTF-8 (variable length multi-byte), and allows the use of 8-bit
access to the ISO Latin 1 set.

Any restrictions on the use of ISO/IEC 2022 switching controls?

Any character
encodings (CGM "character sets") used in the metafile which is
accessed by ISO/IEC 2022 switching techniques shall be in the
character set list (defined in this profile).

Other: See 3.1.1
for additional restrictions to the character repertoire for those
WebCGM non-graphical strings which may be part of the WebCGM IRI
fragment.

Note. According to the Binary Encoding of CGM:1999, strings of
multi-byte Unicode text are "big-endian", like the rest of the binary
metafile.

Maximum string length (bytes):

for type SF: 254.

for type SF within type D: 1024.

Format effectors and ESC: Permitted Yes;
Prohibited No;

Other C0 control codes (except NUL and ISO/IEC 2022 switching) are
prohibited.

Any limits on the set of acceptable character sets? The
permitted character sets are ISO 8859-1 LHS No.1 and ISO 8859-1 RHS
No.1.

Any restrictions on the use of ISO/IEC 2022 switching controls?

Any character set used in the metafile which is accessed by
ISO/IEC 2022 switching techniques shall be in the character set list
(defined in this profile).

Number of occurrences of these elements allowed in the metafile:
No limit.

Other: None.

T.15.3

Same as Model Profile:
No

BEGIN SEGMENT

END SEGMENT

[v2]

References:

7.2.6

7.2.7

Element is: Required
No; Permitted No; Prohibited
Yes;

Maximum number of simultaneously defined segments (both global and
local) at any point in the metafile:

Any limits on the number of elements or restrictions on which
elements compose a segment?

Is there any meaning given to the segment identifier
parameter? (yes/no)

If yes, specify. (Meaning shall have no graphical effect.)

Other: None.

Element is: Required
No; Permitted Yes; Prohibited
No;

Maximum number of simultaneously defined segments (both global and
local) at any point in the metafile: 1024.

Any limits on the number of elements or restrictions on which
elements compose a segment? None.

Is there any meaning given to the segment identifier
parameter? (yes/no) No.

If yes, specify. (Meaning shall have no graphical effect).

Other: When global segments are specified in the Metafile
Descriptor, all global segment definitions shall follow all other
Metafile Descriptor elements. When segments are specified in the
Picture Descriptor, all such segment definitions shall follow all
other Picture Descriptor elements.

T.15.4

Same as Model Profile:
No

BEGIN FIGURE

END FIGURE

[v2]

References:

7.2.8

7.2.9

Element is: Required
No; Permitted Yes; Prohibited
No;

Limits on the number of elements or restrictions on which elements
comprise a figure definition: Maximum number of elements =
1024. No restrictions on which eligible elements may be
included.

Other: None.

Element is: Required
No; Permitted Yes; Prohibited
No;

Limits on the number of elements or restrictions on which elements
comprise a figure definition: Maximum number of elements = 128.
No restrictions on which eligible elements may be
included.

Other: None.

T.15.5

Same as Model Profile:
No

BEGIN PROTECTION REGION

END PROTECTION REGION

[v3]

References:

7.2.10

7.2.11

Element is: Required
No; Permitted Yes; Prohibited
No;

Maximum number of simultaneously defined protection regions:
1.

Maximum number of elements within each protection region:
128.

Is there any meaning to the region index parameter other than as a
unique identifier for each protection region? (yes/no)
No.

If yes, specify. (Meaning shall have no graphical effect).

Other: Region index is restricted to the value
"1".

Element is: Required
No; Permitted Yes; Prohibited
No;

Maximum number of simultaneously defined protection regions:
32.

Maximum number of elements within each protection region:
128.

Is there any meaning to the region index parameter other than as a
unique identifier for each protection region? (yes/no) No.

If yes, specify. (Meaning shall have no graphical effect).

Other: None.

T.15.6

Same as Model Profile:
Yes

BEGIN COMPOUND LINE

END COMPOUND LINE

[v3]

References:

7.2.12

7.2.13

Element is: Required
No; Permitted Yes; Prohibited
No;

Limits on the number of elements and identity of elements
comprising a path definition: Maximum number of elements is
128. No restrictions on which eligible elements may be
included.

Other: None.

T.15.7

Same as Model Profile:
Yes

BEGIN COMPOUND TEXT PATH

END COMPOUND TEXT PATH

[v3]

References:

7.2.14

7.2.15

Element is: Required
No; Permitted Yes; Prohibited
No;

Limits on the number and identity of elements comprising a path
definition: Maximum number of elements is 128. No restrictions
on which eligible elements may be included.

Other: None.

T.15.8

Same as Model Profile:
No

BEGIN TILE ARRAY

END TILE ARRAY

[v3]

References:

7.2.16

7.2.17

Element is: Required
No; Permitted Yes; Prohibited
No;

Maximum number of tiles in path direction: 64

Maximum number of tiles in line direction: 64

Maximum number of cells/tile in path direction:
4096

Maximum number of cells/tile in line direction:
4096

Limits on pel path: shall be 0.

Limits on line progression: None.

Limits on image offset: None.

Other: Two types of raster images are allowed. A single
(non-tiled) image has a maximum of 1,073,741,824 (1 giga, 32768**2)
cells. A non-tiled image may exceed the 4096 cells/tile restriction
specified for the tiled images. Tiled raster images are limited 64X64
tiles which are a maximum of 4096X4096 cells each. These tiled images
are limited to a total of 1,073,741,824 (1 giga, 32768**2) cells
(adjustment of maximum number of tiles and cells per tile are
necessary to meet this requirement).

Element is: Required
No; Permitted Yes; Prohibited
No;

Maximum number of tiles in path direction: 16.

Maximum number of tiles in line direction: 16.

Maximum number of cells/tile in path direction:
1024.

Maximum number of cells/tile in line direction:
1024.

Limits on pel path: None.

Limits on line progression: None.

Limits on image offset: None.

Other: None.

T.15.9

Same as Model Profile:
No

BEGIN APPLICATION STRUCTURE

BEGIN APPLICATION STRUCTURE BODY

END APPLICATION STRUCTURE

[v4]

References:

7.2.18

7.2.19

7.2.20

Element is: Required
No; Permitted Yes; Prohibited
No;

Limits on the maximum number of defined structures within a
picture:None.

Limits on the number and identity of elements comprising a
structure: None.

Is there any meaning to the Application Structure (APS) identifier
parameter? yes/no No. No assigned meaning beyond being a
unique identifier for the application structure.

If yes, specify. n/a

Is the inheritance flag parameter restricted? Yes/no: Yes.
The value of the inheritance flag is restricted to a value
corresponding to "statelist".

Other: The value of the structure type parameter must be chosen
from the list of valid structure types listed in the Section 3.2.1. Structures
are placed in the metafile according to the EBNF content model
fragments in Section
3.2.1 and its subsections. The character repertoire of the APS id
parameter is identical to that of the objid production
as defined in Section
3.1.1.3.

Element is: Required
No; Permitted Yes; Prohibited
No;

Limits on the maximum number of defined structures within a
picture: None.

Limits on the number and identity of elements comprising a
structure: None.

Is there any meaning to the application structure identifier
parameter? yes/no No. No assigned meaning beyond being a
unique identifier for the application structure.

The description parameter shall follow the rules for
non-graphical text, clause 9.5.4.6 and T.14.5. The substring within the SF
parameter shall be of the form: "keyword:item", where the double
quotes are part of the substring.

Refers to the approved version and revision of the
specification that applies for this graphic. The Item associated with
the keyword ProfileEd shall be n.m. For this WebCGM Edition:
"ProfileEd:2.0".

Additional information content:

Metafile colour conformance class, source, and date items shall be
encoded as substrings of the description parameter using the
keywords: "ColourClass:", "Source:", and "Date:", respectively.

ColourClass: Required Yes;

Content: One of "ColourClass:monochrome" or
"ColourClass:colour".

Source? Required No; Permitted
Yes;

Content: "Source:supplier"

Date? Required No; Permitted
Yes;

Content: "Date:yyyymmdd"

Other: Parameter strings are considered case
insensitive.

Element is: Required
Yes;

The description parameter shall follow the rules for
non-graphical text, clause 9.5.4.6 and T.14.5. The substring within the SF
parameter shall be of the form: "keyword:item", where the double
quotes are part of the substring.

All font indexes referenced in the metafile, including the default
(nominally index 1) shall be defined in the FONT LIST element, with
font name construction consistent with the rules of ISO/IEC 9541.

List of recommended fonts:

Times-Roman

Times-Bold

Times-Italic

Times-BoldItalic

Helvetica

Helvetica-Bold

Helvetica-Oblique

Helvetica-BoldOblique

Courier

Courier-Bold

Courier-Oblique

Courier-BoldOblique

Symbol

NOTE - Theses font names are trademarked and some are proprietary
and copyrighted. Times and Helvetica are registered trademarks of
Allied Corporation, the owner of the copyright on the fonts of those
names. Metric equivalents of the named fonts may be substituted by
interpreters. Times is a serif font. Helvetica is a sans-serif font.
Courier is a monospaced, serif font. The association of character
code to glyph which shall be used for each of the fonts and the
metrics of the named fonts are contained in clause I.2, annex I of
CGM:1999.

Other: The list of recommended fonts is intended to be a
list of required minimum interpreter font capability and a
recommended maximum font capability for generators. If other fonts
are used, the FONT PROPERTIES and RESTRICTED TEXT elements are
required. Font names are considered case insensitive.

Element is: Required
No; Permitted Yes; Prohibited
No;

This element is required for all metafiles containing graphical
text.

Maximum number of fonts in the list: 64.

All font indexes referenced in the metafile, including the default
(nominally index 1) shall be defined in the FONT LIST element, with
font name construction consistent with the rules of ISO/IEC 9541.

List of permitted fonts:

Times-Roman

Times-Bold

Times-Italic

Times-BoldItalic

Helvetica

Helvetica-Bold

Helvetica-Oblique

Helvetica-BoldOblique

Courier

Courier-Bold

Courier-Oblique

Courier-BoldOblique

Symbol

NOTE - Theses font names are trademarked and some are proprietary
and copyrighted. Times and Helvetica are registered trademarks of
Allied Corporation, the owner of the copyright on the fonts of those
names. Metric equivalents of the named fonts may be substituted by
interpreters. Times is a serif font. Helvetica is a sans-serif font.
Courier is a monospaced, serif font. The association of character
code to glyph which shall be used for each of the fonts and the
metrics of the named fonts are contained in clause I.2, annex I.

Note. The terminology "character set", used in the original
ISO CGM:1987 specification and preserved through CGM:1999, is
considered inaccurate by contemporary standards. The current correct
terminology is character
encoding, defined in the [CHARMOD]
standard.

Maximum limit for the number of character sets in the character
set list: 6.

Allowable character sets:

"94-character G-set", 4/2 (ISO 8859-1 LH);

"96-character G-set", 4/1 (ISO 8859-1 RH);

"94-character G-set", 2/10 3/10 (Symbol LH);

"94-character G-set", 2/6 3/10 (Symbol RH);.

"complete code", 2/15 4/9 (UTF-8)

"complete code", 2/15 4/12 (UTF-16)

Note. The tails for UTF-8 and UTF-16 differ from their WebCGM
1.0 values. 2.0 metafiles shall not use the 1.0 forms.

If any of these character sets is of type "complete code", specify
the content of the complete code and its associated sequence tail:
Specified

Other: None.

Element is: Required
No; Permitted Yes; Prohibited
No;

This element is required for all metafiles containing graphical
text.

Maximum limit for the number of character sets in the character
set list: 4.

Character sets shall be selected from the ISO Registry of
Character Sets. This list may be extended by adding profile-defined
character sets. List character sets:

"94-character G-set", 4/2 (ISO 8859-1 LH);

"96-character G-set", 4/1 (ISO 8859-1 RH);

"94-character G-set", 2/10 3/10 (Symbol LH);

"94-character G-set", 2/6 3/10 (Symbol RH).

If any of these character sets is of type "complete code", specify
the content of the complete code and its associated sequence tail:Not applicable.

Other: None.

T.16.15

Same as Model Profile:
No

CHARACTER CODING ANNOUNCER

[v1]

References:

7.3.15

Element is: Required
Yes;

Any restrictions on the parameter values? Value shall be
'basic 8-bit'.

Other: None.

Element is: Required
No; Permitted Yes; Prohibited
No;

Any restrictions on the parameter values? Values shall be
'basic 7-bit' and 'basic 8-bit'.

Other: None.

T.16.16

Same as Model Profile:
No

NAME PRECISION

[v2]

References:

7.3.16

Part 3, 8.3

Part 4, 7.2

Element is: Required
No; Permitted No; Prohibited
Yes;

The parameter value of this element is coding dependent.

If binary encoding is permitted, are there any restrictions on the
parameter value? n/a.

Other: n/a.

If clear text encoding is permitted, are there any restrictions on
the parameter value? n/a.

Other: n/a.

Element is: Required
No; Permitted Yes;

The parameter value of this element is coding dependent.

If binary encoding is permitted, are there any restrictions on the
parameter value? 8 or 16.

Other: None.

If clear text encoding is permitted, are there any restrictions on
the parameter value? 127, 255, 32767.

If binary encoding is permitted, are there any restrictions on the
Parameter value? 16 or 32.

Other: None.

If clear text encoding is permitted, are there any restrictions on
the parameter value? [-32767,32767], [-32768, 32767], or
[-2147483648,2147483647].

Other: None.

T.18.2

Same as Model Profile:
Yes

VDC REAL PRECISION

[v1]

References:

7.5.2

Part 3, 8.5

Part 4, 7.4

Element is: Required
No; Permitted Yes;

The parameter values of this element are encoding dependent.

If binary encoding is permitted, are there any restrictions on the
Parameter value? (1, 16, 16) or (0, 9,
32)

Other: None.

If clear text encoding is permitted, are there any If clear text
encoding is permitted, are there any restrictions on the parameter
value? 0.0, 1.0 , 4; or -32767, 32767, 4; or -32768,
32767, 10; or -3.4028235E38, +3.4028235E38, 8

Note: The latter two values are the closest
approximation, in base 10 clear text, to the REAL PRECISION values
allowed in binary encoded CGMs.

Accuracy and latitude for mapping
application graphics to CGM graphical primitive elements: Accuracy
and latitude for mapping application graphics to CGM graphical
primitive elements: Generators shall produce a metafile whose
graphical primitive elements match the application graphical
primitives accurately to within Â±0.1% of relative position within the
VDC Extent box or Â±1/2 pixel of the intended size, whichever is
greater. Generators shall produce geometric size aspects of the
primitives (e.g., text size, line width, and edge width) to within 1%
of the intended size or Â±1/2 pixel of the intended size, whichever is
greater.

This requirement shall apply to all graphical
primitive elements, unless superseded by specific element
requirements in this clause.

T.25.3

Same as Model Profile:
Yes

Text accuracy and latitude

References:

9.5.6.2.3

Is text accuracy and latitude
addressed? (yes/no) Yes.

If yes, specify. Metafile text specifications shall match
the text of the application picture to within Â±1% of relative to the
intended size or Â±1/2 pixel of the intended size, whichever is
greater, for the placement and overall extent of each text
string.

Drawing priority and mode:
Priority shall correspond to the metafile order (i.e.,
primitives occurring later in the file shall overlay primitives
occurring earliest in the file). Mode shall be "replacement"
mode.

Clipping: Clipping shall be to the intersection of the clip
rectangle, the VDC EXTENT, the device viewport, and the device view
surface limits.

Edge centreing: Edges shall be centred on the ideal
mathematically-defined edge of the area

Meaning of predefined line types and edge types: See Section
6.16 about specific and generic line
types.

Drawing priority and mode:
Priority shall correspond to the metafile order (i.e.,
primitives occurring later in the file shall overlay primitives
occurring earliest in the file). Mode shall be "replacement"
mode.

Clipping: Clipping shall be to the intersection of the clip
rectangle, the VDC EXTENT, the device viewport, and the device view
surface limits.

Edge centreing: Edges shall be centred on the ideal
mathematically-defined edge of the area.

Meaning of predefined line types and edge types: The exact
on-off definitions for the predefined line types and edge types are
not specified.

Meaning of predefined hatch styles:The inter-line spacing is
not specified. Use the latitudes of annex D.4.6.16 for the angular
directions.

Accuracy and latitude for placement and
realization of geometric aspects when geometric primitive elements
are rendered. Interpreters shall render graphical primitive
elements accurately to within Â± 0.1% of relative position within the
VDC Extent box or Â±1/2 of the pixel resolution of the output device,
whichever is greater. Interpreters shall render the geometric size
aspect of primitives (e.g., text size, line width, and edge width) to
within 1% of the intended size or Â±1/2 pixel of resolution of the
output device, whichever is greater.

This requirement shall apply to all graphical primitive elements,
unless superseded by specific element requirements in this clause.

T.26.5

Same as Model Profile:
Yes

Text rendering

References:

9.5.7.4.3

Is text accuracy and latitude
addressed? (yes/no) Yes.

If yes, specify. Interpreter-rendered text shall match
the text specification of the metafile to within 1% relative to the
intended size or Â±1/2 pixel of resolution of the output device,
whichever is greater, for the placement and overall extent of each
text string.

Is precision of text rendering is addressed? (yes/no)
Yes.

If yes, specify interpreter action. Interpreters shall
render text using 'stroke' precision, regardless of the actual value
of the TEXT PRECISION of the metafile.

Drawing priority and mode:
Priority shall correspond to the metafile order (i.e.,
primitives occurring later in the file shall overlay primitives
occurring earliest in the file. Mode shall be "replacement"
mode.)

View surface clearing at picture start: Surface will be
cleared upon the occurrence of BEGIN PICTURE BODY, except as
specified elsewhere in this profile.

Clipping: When CLIP INDICATOR is 'off', clipping shall be to
the intersection of the device viewport and the device view surface
limits. When CLIP INDICATOR is 'on', clipping shall be to the
intersection of the clip rectangle, the VDC EXTENT, the device
viewport, and the device view surface limits

Edge centreing: Edges shall be centred on the ideal
mathematically-defined edge of the area.

Meaning of predefined line types and edge types: See Section
6.16 about specific and generic line
types.

in the style of one specific parameter value, from the set of
standard and registered values (excluding value 1) of the EDGE
TYPE CONTINUATION element. No Value = ?

in the style of any parameter value, from the set of standard
and registered values (excluding value 1) of the EDGE TYPE
CONTINUATION element. Yes

Other: Mitre Limit handling: The
handling of MITRE LIMIT in CGM:1999
6.5.6 is considered to contain errors, and an ISO erratum is being
pursued. The following variation shall be considered conforming for
the WebCGM profile, and is the preferred method when mitred line
joins are rendered.

When the projected join point would exceed the mitre length,
measured from the intersection of the inside edges of the lines
at the join, then the join is rendered as a bevel style.
(CGM:1999 says that the projecting point is truncated at the
mitre length).

Any value of MITRE LIMIT that is less than 1.0 shall be mapped
to 1.0.

Drawing priority and mode:
Priority shall correspond to the metafile order (i.e.,
primitives occurring later in the file shall overlay primitives
occurring earliest in the file. Mode shall be "replacement"
mode.)

View surface clearing at picture start: Surface will be
cleared upon the occurrence of BEGIN PICTURE BODY.

Clipping: When CLIP INDICATOR is 'off', clipping shall be to
the intersection of the device viewport and the device view surface
limits. When CLIP INDICATOR is 'on', clipping shall be to the
intersection of the clip rectangle, the VDC EXTENT, the device
viewport, and the device view surface limits.

Edge centering: Edges shall be centred on the ideal
mathematically-defined edge of the area.

Meaning of predefined line types and edge types: The exact
on-off definitions for the predefined line types and edge types are
not specified.

Meaning of predefined hatch styles: The inter-line spacing
is not specified. Use the latitudes of annex D.4.6.16 for the angular
directions.

In the absence of a LINE/MARKER/TEXT/EDGE CLIPPING MODE element,
the interpreter treatment of LINE/MARKER/TEXT/EDGE CLIPPING MODE
shall be (check one):

In the style of one specific parameter value, from the set of
standardized values. No. Specify which one:

In the style of any of the specific parameter values, from the set
of standardized values. Yes. Specify which one:

For [v1/v2] metafiles, text restriction method for RESTRICTED TEXT
elements, chosen from the set of standard and registered styles of
the RESTRICTED TEXT TYPE element: Value 2.

For [v1/2] metafiles, interpreter treatment of the 2 aspects of
line cap shall be either:

No; in the style of one specific parameter
value pair from the set of standard and registered values
(excluding values 1) of the LINE CAP element. Values = ?

Yes; in the style of any parameter value pair
from the set of standard and registered values (excluding values
1) of the LINE CAP element.

For [v1/2] metafiles, interpreter treatment of the 2 aspects of
edge cap shall be either:

No; in the style of one specific parameter
value pair, from the set of standard and registered values
(excluding values 1) of the EDGE CAP element. Values = ?

Yes; in the style of any parameter value pair,
from the set of standard and registered values (excluding values
1) of the EDGE CAP element.

For [v1/2] metafiles, interpreter treatment of line join shall be
either:

No; in the style of one specific parameter
value, from the set of standard and registered values (excluding
value 1) of the LINE JOIN element. Value = ?

Yes; in the style of any parameter value, from
the set of standard and registered values (excluding value 1) of
the LINE JOIN element.

No; in the style of one specific parameter
value, from the set of standard and registered values (excluding
value 1) of the EDGE TYPE CONTINUATION element. Value = ?

Yes; in the style of any parameter value, from
the set of standard and registered values (excluding value 1) of
the EDGE TYPE CONTINUATION element.

Other: None.

T.26.8

Same as Model Profile:
Yes

Error processing

References:

9.5.7.6

Is error processing addressed? (yes/no)
No.

If yes, specify the action taken.

Classification of error severity?

Requirements for error recovery?

Requirements for error reporting?

Additional areas?

Other: None.

T.26.9

Same as Model Profile:
Yes

Reporting

References:

9.5.7.7

Is reporting required? (yes/no)
No.

If yes, specify the action taken.

Method and format of the reporting?

Requirement to report any substitution, error, fallback behavior,
mappings, or other behaviors?

Additional areas?

Other: None.

T.26.10

Same as Model Profile:
Yes

Degeneracies

References:

9.5.7.8

9.5.4.4

D.2

D.4

Is the interpretation of degenerate
primitives addressed? (yes/no) Yes.

If yes, for each primitive, specify the degeneracy including its
source (i.e., intrinsic or computational). Intrinsically
degenerate primitives shall be rendered as specified in annex D
subsections: D.2.2, D.2.3, D.4.5.4 through D.4.5.8, D.4.5.11, and
D.4.5.12. Interpreters are not required to detect computational
degeneracy. If interpreters do detect computational degeneracies,
they shall be rendered as specified in annex D subsections: D.2.2,
D.2.3, D.4.5.4 through D.4.5.8, D.4.5.11, and D.4.5.12

Other: None.

T.26.11

Same as Model Profile:
Yes

Transparency

References:

7.5.3

7.5.4

T.18.4

If Transparency permitted specify
interpreter behavior: Interpreters shall implement the
AUXILIARY COLOUR and TRANSPARENCY elements as described in the 2nd
and 3rd paragraphs of the description in 7.5.4.

Other: None.

T.26.12

Same as Model Profile:
No

INTERPRETATION OF STRUCTURES AND
DIRECTORIES

[v4]

References:

Any requirements on the interpretation of
the application structures? Interpreters shall produce
the correct graphical results.

WebCGM supports both generic, but imprecise line types, and specific,
precise line types. The realizations of line types 1..5 are described in
general terms in the CGM standard (e.g., "dash-dot-dot"), and the
realizations and constraints of the registered line types 6..15 are described
in the ISO Register of Graphical Items (e.g., requirements for inking
vertexes in certain engineering line types). Otherwise, the exact line
patterns of implicit line types 1..15 are unconstrained. Where exact
realizations of line types are expected and required, the LINE AND EDGE TYPE
DEFINITION element should be used.

WebCGM supports both generic, but imprecise hatch styles, and specific,
precise hatch styles. The realizations of hatch styles 1..6 are described in
general terms in the CGM standard. Otherwise, the exact hatch patterns of
implicit hatch styles 1..6 are unconstrained. Where exact realizations of
hatch styles are expected and required, the HATCH STYLE DEFINITION element
should be used.

This profile allows the use of JPEG restricted to the TILE element. The
method is limited to BASELINE JPEG. BASELINE JPEG conforms to the process
required for all DCT-based decoders. The colour selection mode of the TILE
element shall always be direct, independent of the COLOUR SELECTION MODE in
effect in the CGM. The cell colour precision parameter of the TILE shall
always be 8-bit for BASELINE JPEG. The COLOUR model of the TILE element shall
be defined in the method specific parameters element of the TILE. It can be
the same or independent of the COLOUR MODEL of the CGM. BASELINE JPEG shall
assume that the order of the spectral bands is the same order given by the
colour model as defined by the method specific parameters. For example, if
the model is RGB, each scan will compress the red component, followed by the
green component, followed by the blue component. For the case where the
colour model is "RGB related", the specific colour model shall be defined in
the method specific parameters of the TILE element. The method specific
parameters shall be present for each image compressed using BASELINE JPEG.
The parameters shall be encoded as an SDR. The JPEG colour model parameter is
required and is specified according to the rules of the INDEX PRECISION
element. Valid values are:

0 - JPEG colour model is the same as the COLOUR MODEL of the CGM.

1 - RGB

2 - CIELAB

3 - CIELUV

4 - CMYK

5 - RGB related

Values outside the range of 0-5 are not allowed. The JPEG colour submodel
is required only when the JPEG colour model is "RGB related" and is specified
according to the rules of the INDEX PRECISION ELEMENT. Valid values are: